Core drill bit



` A slMoNs y2,304,482

` CORE DRILL BIT Filed Nov. 27, 19:59

` n INVENTO;

` ,4A/POM g@ ai f a 1 1- ATTORNEY.

PatentedDec-Ls, y1942 i Q I UNirED .-srArEs PATENT, OFFICE f l2,304,4sz' *i y Q Y i conannmnmr l i y Simongronx, Y. limitationNovember 27, 1939, semi N5. 306,224

" achim. (01.255412) This invention relates to core bits and similarbeing drilled is somewhat rldged because the tools, rother mountingmembers wherein dia-` `amends do not all overlap and do not presentmonds `orsnfiall particles of other extremely Ahard a continuouscutting'edge, butleave some spaces substlances are ,mounted inY thesurface of the` that are not acted upon by any diamond, "mounting memberto expose partsuof `the dia- 5 In drilling with a. conventional diamondcore mondsor othertelement -through said surface. y drill bit havingrandom or staggered diamonds, More-particularly the inventionconsistslin a tool the Sludge' oWS around andV between the diaor memberofthecharacter described wherein amonds, and being abrasive, tends t0erode the series of elementsare v.arrangedin contiguous ar-l` 1 `metalaround each diamond, thereby loosening l rangement or in `edge toedgeandabutting rela-` lo the diamonds from their mountings. Ina diatlonship onthe surface ofthe tool and in a prede-` mond core drill bit constructedin accordance y terminedarrangement thereon to provide ofV the With myinvention, the Sludge will'impinge upon series of elements,substantially continuous cutter the leading Side of each row ofdiamonds. The blades extending over the surface of the tool body IQWSare. arranged at vSuch Suitable angle as to` or member. The` novelfeatures of the invention l5' Cause the impinging Sludge to bedeflected` out-fwill be best understood from `the following de- Wardly.The erosive action ofthe sludge, therescription when taken together withthe accomfQle. Will be Communicated GnlY i0 the leading panying drawing,inwhich certain embodiments side of each diamond and not to its othersides, of the-,invention aredisclosed, and in which the S0 that iPhedialnOndS `Will have Inlleh less separate Vpartsare `designated bysuitable ref- 20 tendency t0 be lOOSened from their menntlnSS.

i erence characters in each of the `viewsyfand in thereby greatly addingto the life of the drill bit.

which: j .Y I i Figi is aside and sectional view of a `core drill bitwas individually'mounted by hand, 1ndrill ,bit made according to myinvention, the volving considerable expense and requiring largesectionbeing substantiallyon the line I--I oi'` 2l diamonds `permittingOnly a feW diarriende t0 l Figi be set in each bit. Lately mechanicallyset bits` l gFig. 2`is a plan view of the core drillbit as seen havecome into Wide use- 'Tiiese can be made lngplg` 1; l l l with a largenumber of small diamonds. AVarious `lig. 3 is a side and sectional `viewsimilar to methods 0f mounting diamonds mechanically in Fig.V 1, "butshowing the use of a separate ring or "i0 coredrill bits have beendevised, but none of them l clp-own mounted on 3 threaded shank, is ableto securely mount aA row of diamonds in Figli is an `enlarged sectionaldetail view illus- Contact with each other, and all present methodstralilng the mounting of a Irow 0f diamonds, the y of mounting areunsatisfactory because the diasection being on the line lf-l of Fig. 2.`monds must be spaced apart and are not always Eig-5 isan enlargedsectional detail view simi- 35 ilrmiy gripped iii the mounting and theirOuter lar to Fig. 4 but` showing a. modification, l edges do not alwaysprotrude equally from the Fig; 61S a View Similar t Fig. 4 but showlngmounting.v Various kinds of mountings have been another modification. l

Figkr is e view similar to Fig. ishowing a i monds Securely in i001steelfurthefmodlcatlomand Y l 40 In my invention diamonds or otherelements Fiig 8 j s a pal-tial sectional Vjew of a workpiece le arrangedln lOWS, 81nd the diamonds .ln ch and forming die illustrating lthemethod of prorow are contiguous and in contact with each other ducingresulting tools as shown, in the other l and alie net ,spaced apart.blltthe rows are spaced flgures- K apart with reference to Aeach other.VBy this arn theconventional `diamond core drill bit, the 45 rangementthe diamende 01'` elements form condlamollds are set at random or arearranged l'n` tinuous` cutters or cutting edges, and the cuts concentricrings, or in staggered concentric rings, made by the diamonds OVeliap.leavingV theY cut' with relationto the diamonds in the other rings,` iyadding t0 ,the emciency and Cutting Speed of or are arranged 1nV otherdisposition,` but 50 the Upon Core the I'OWS 0f elein all cases thediamonds are separated from each ments may be arranged radial er from aradlal other bysubstantialspacings. Each diamondacts t0 aV tangentialanglllarlty. and it is preferred as a separate cutting tooth but thearrangement that an angularity between radial and tangentialseldomresults in a smooth oruniiorm cut, but be employed.

on the contrary, the cut surface of the substance 5 With my invention itwill be apparent that the orother elements fmay be mounted directly inthe tool or other member regardless of Y the material employed therein,it being understood thatV tool steel is preferred in most Yuses.

contiguous arrangement in row'sl'or any other de-I -sired manner so asto provide the desired cutter VVblades on the resulting tool..

In Figs. 1 and 2 of the drawing, the drin bit vFurthermore the elementsmay be mounted in I0 is provided with a rounded or domed working 10diamond.orotherhard cutter elements I2 which are mounted Iin accordancewith the method forming the subject matter of a companion applicationi'lled by me of like date herewithandA- ,15"

hereinafter described, and illustrated inpart in Fig. 8 of the drawing.v

`The elements I2 are arranged ina series .o f

rows I3 lwhich are spaced circumferentially around the domed end II.\ 1The elements I2 in '2o' each row are contiguous and in contact `witheach other; andall ythe 'elements' I2 `in all the rows'fprotrudelequally from the surface of the domedv endl I. The rows are notvgeometricallyl radial but are'set 'atanv` angle tothe true radii, 25

soathat'wheri'the' bit rotates, the inner diamond isf'orwardV and the:router diamond's further to therear.V This angle isso arranged;v thatwhen the drill bit rotates in the drill hole, the sludge ous `forms inwhich monds or other cutting elements. In Fig.'4 they elements V3|) areimbedded in theV drill or other mounting member 3I. This member l3lcorresponds to the domed end II of the bit I0 in Figs. l and 2 or thedomed end26 of the crown 23 in Fig. 3. Theinner dotted line 32 indicatesthe' outer surface of the member 3| showing its level between theA rowsof diamonds, and `the outer ydotted line 32a. indicatesjtheouteredgeoftheY mounted diamonds showing that they protrude 4 equally from thesurface of the member. It will also be noted that the major portion ofeach diamond is rmly imbedded in the member, only a small portionprotruding therefrom. I

In Fig". V5, 3Ia represents Va part of a drill bit whichy isrectangularin cross sectional form', and' ar`represents the diamondsimbedded therein. The forms shown in Figs. 4 and5 are.` more ,or

less conventional, whereas vFigsf-andf'l illus-f impin'ges upon theleading side o f eachk row I3 30 of diamonds at al suitable angle tobe'l deflected outwardly@ kAs allthe diamonds protrude .equal-` ly'fromthe surface II', the end diamonds of each rw'protrudefequally from thewallsof the bit massimi/nv at I4. VThe quier wan of the bam as ispreferably tapered as atr I5 to provide a clear passage kforthe return`flowof water andwsludge Y around the drilling pipeor core-barrel`partially indicated at YIii to which the bit IU. isconnected.

The `shankportion lI1 of the bit I0oppositethe domedjen'd I I isthreadedas at I8 inthe usual manner for' connection vwith the drillingpipe or core-barrel.'

In Fig. 3` of thedrawing, I have shown v2|) the shank portionof a.Adrill bit which is threaded as at`2I similar tot the threaded portionlI8` shownin Figgl of the drawing. Theotherendv4 ofthe shank'p'ortion 20is a surface 22 adapted 23 maybefattached ,and removed at-@willn I-n thelattercase the `surfacen22 of the shanklll and themountin'g portion24 ofthe crown..23'may bothbe threaded `sothat they may be detachably lconnected rby' being screwed together, or these parts may be detachablyconnectedby pins, vone of whichis indicated at 25. A permanent con'-nectin can: be obtained by, rivetingor welding thetwo'parts together, orthe crown :23"'can be directly and'immovably forged upon the shank 20inthe/manner hereinafter described. The outer portion `of the crown 23is provided withY a rounded or domed working end'2l6 in f which areimbeddedthediamonds or other 'cut-T ting elements21 in aseries of rows28', ymounted contour ofthe depression 35 inthe die 34 to the l desiredshape. The grooves 36 will controlthe and arranged in the same manneras' the cutting 70 elements I2in Figs. 1 and 2. The crown may taperedasv at 29 `for the same purpose-as the taper` I5in'F'iE. 1"."1

In. Figs, 4, 5,k 6 and 'z-,of thadrawingare shown u enlarged detailviews. in section, showinglvaritrate other forms of mounts which can beein, y

ployed. InFig. `6, 3Ib represents what maybev termed a tapered orconical` cross sectionalV lcon'- tour, the diamonds being ishownat301),*- In 7 of the drawing a` beveled cross sectional forni` of bitisshown at 3Ic with the diamonds 36e imn bedded therein. The formsof bitshown in I Figs.-6 yand '1 are more efficient due to the fact that theypresent a leading cutting edge vengaging the substances or materialbeing drilled,- thereby easing the 'drilling operation.

vIn Fig. 8I`have indicated diagrammaticallyl the vprocess oi formingtools of the type and kind shown in'Figs. l to '7 inclusive, being the'method more vfully described'in and beingthe subject matter of' acompanion application filed by 'me' 1 of like datefherewith. Inthisfigure, 33 represents a part of a workpiece or blank of tool steel.

or other suitable material, from which` the 1resulting tool 'is to vbeformed. Adieor punch is.vl shown at 34 having an annular depression'jor?cavity 35 in the lower yportion thereof which has anjappropriate crosssectional contour.' In this annular depression are a Aseries' of grooves36st. circumferentially spaced intervals. The grooves 36 are arranged atthe desired angle tothe radii. In each groove 36 is placed. a contiguousrovi/of diamonds or othery cutting elements 31, similar to the elementsI2, 21fand 30. 'Shellac, glue, gel# atin or the like 38 may be used as acementing substance.l to hold the elements l31 in position.A

The prepared die with the'diamonds in `position is now placed in themovlngmember of a forging press. The workpiece 33 `is then heated in lasuit-A able furnace; to a forging temperature, andwhile Y at thistemperature is placed on a shank 39 and...A

securely imbedded in the forged tool. The cross vsectional contour ofthe nished surface 33a can be made of any shape, such for example as'shown in Fig. 4, 5, 6 or '7,'by shaping the cross sectional outer Vedgesof the diamonds 31, so that they will protrude equally from the vsurface33a ofi the forged tool. The amount by which thediamonds 31 protrudefrom the surface 33a may be regulated bymaking the grooves 36 deeperorshalf-` lower. Y Y V v v the working end of `the drill y .y bit may beshaped, and illustrating a row of dia- The die is now pressed upon ,the

signatur.: 52r

If it is desired rigidly to forge a crown 23 upon a shank 20 in Fig, 3,the blank or workpiece 33 is suitably preformed as in Fig. 8 and theshank 39 and the blank 33 are both placed in a properly formedreceptacle or cup 40 on the bed of the forging press. TheY portion 4| ofthe shank 39 in' Contact with the blank 33, may be grooved or threaded,so that upon forging, the metal of the blank 33 may be forced into theseirregularities ofsurface to create a tight bond between the two parts. l

Although I have described a diamond core drill bit, this invention isalso applicable to abrasive wheel dressers or other tools where it isdesired to mount diamonds or other hard substance in rows on a curved orflat surface of a metallic member or other suitable material. For theseuses a single row of diamonds or other cutting elements may be'imbeddedin a suitably shaped member. The shape of the nished tool can bedetermined by the shape of the die.

For the purpose of simplifying the language of the claim it is herestated that in referring to angular arrangement of rows of the cutterele ments, that reference is made to an arrangement between a trueradial andsubstantially a tangential position on thesurface of thetubular tool cross sectional contour, a plurality of rows of t uncutdiamonds Vimbedded in `said domed end, each row being arranged at apredetermined and like angle, and the diamonds in each row beingarranged in contact to form substantially continuous cutters of each rowof diamonds.

, AARON SIMONS.

